Pivots for rotary surfaces

ABSTRACT

Two or three sheets of strong paper, cardboard or any other suitable material are joined so that they can rotate relatively to each other by impressing upon an inner sheet a centrally located circular area and firmly connecting it to a similar area located upon another sheet. Then the circular area of the inner sheet can be separated to form a disc and the inner sheet can be rotated around that disc. The central area or areas of the outer sheet or sheets can be embossed to form projecting areas firmly connected with the rotary disc of the central sheet.

United States Patent Primary Examiner-Robert W. Michell Assistant Examiner-L. R. Oremland A!t0rney- Richards & Geier ABSTRACT: Two or three sheets of strong paper, cardboard or any other suitable material are joined so that they can rotate relatively to each other by impressing upon an inner sheet a centrally located circular area and firmly connecting it to a similar area located upon another sheet. Then the circular area of the inner sheet can be separated to form a disc and the inner sheet can be rotated around that disc. The central area or areas of the outer sheet or sheets can be embossed to form projecting areas firmly connected with the rotary disc of the central sheet.

PATENTED SEPI 4I97I FIG.3

FIG.2

FIG.I

FIG.4

INVENTOR CHARLES F. CLARK B I ATTORNEYS PIVOTS- FOR ROTARY SURFACE;

This invention relates to pivots for rotarysurfaces and refers more particularly to sheet assemblies or dials wherein the sheets can be rotated relatively to each other. Usually in such assemblies the outer sheet is provided with one or more openings, making it possible to read various inscriptions imprinted upon an inner sheet. Such sheet assemblies are widely used for advertising purposes, games, scoring devices, calculators, devices, facilitating the selection of various data, industrial, educational and promotional visual aids and the like. The sheets are usually made of strong paper or cardboard, although transparent material and plastic material are sometimes used. Usually the sheets consist of circular discs of somewhat different diameters, although sheets of other shapes are also used. At the present time the sheets are joined by metal pins, eyelets, grummets or pivots extending through the centers of the sheets. This arrangement is unsatisfactory in that the top sheet which often carries most of the imprinted material, presents an unsightly appearance. The pins or pivots can easily fall off the sheets, thereby terminating the effectiveness of the assembly. The user, when handling the device, can scratch his or her hand upon the projecting ends of pins and pivots.

An object of the present invention is to eliminate these drawbacks of existing constructions.

Another object is the provision of a sheet assembly which is devoid of metal pins and pivots and wherein no means providing the rotation of an inner sheet relatively to the outer sheet are visible upon the outer surface of the outer sheet.

Other objects will become apparent in the course of the following specification.

In the accomplishment of the objectives of the present invention it was found desirable to provide a sheet assembly by initially impressing a circle upon the central portion of the inner sheet. The circular impression should extend through the sheet but in order to prevent the central portion from falling off, small strips are provided joining the central portion with the rest of the sheet. Then this central disc portion is glued to the corresponding inner area of an outer sheet. This gluing operation may be carried out in a number of different ways. For example, the central portion may be covered with a layer of glue, and then the outer sheet may be pressed against the inner sheet. It is also possible to cover with glue a corresponding surface of the inner sheet and then apply the glued area to the cutout portion of the inner sheet. If a glue is used which is effective only by joining two glue layers, both the eutout portion of the inner sheet and the corresponding area of the outer sheet are coated with glue before being joined. After the gluing has solidified, the glued sheets are turned relatively to break off the small strips joining the central disc to the rest of the sheet. Then the central disc will constitute an effective pivot for the rotation of the sheets.

Theoretically this connection can be provided for two sheets, namely, an outer sheet and an inner sheet. However, a connection between only two sheets can easily result in the separation of the sheets. Furthermore, sheet assemblies now in use usually consist of three sheets. The third sheet is connected to the impressed disc in the same manner as the outer sheet, namely, by providing a glue-carrying area upon an inner surface of the third sheet or by applying glue on both surfaces of the inner disc.

According to a further embodiment, the first and third sheets have central areas which are embossed so that they project inwardly in relation to the other portions of the sheets. Then the disc of the central sheet can be conveniently glued to the two projecting portions, thus providing an effective pivot for the central sheet.

It is apparent that the described gluing operations can be replaced by heat sealing or any other suitable joining means.

The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawings, showing, by way of example only, preferred embodiments of the inventive idea.

In the drawing:

FIG. 1 is a front view of a sheet assembly made in accordance with the present invention;

FIG. 2 is a section along the line II-II of FIG. 1, the sheets having been shown as excessively separated for clarity of illustration;

FIG. 3 is a front view of the inner sheet prior to its attachment to the outer sheets;

FIG. 4 shows the inner surface of the outer sheet prior to its attachment;

FIG. 5 is a diagrammatic side view of a somewhat different sheet assembly;

FIG. 6 is a diagrammatic side view of yet another embodiment.

FIG. 1 shows a sheet assembly having a front sheet 10, an inner sheet 11 and a rear sheet 12. In the illustrated embodiment, the front sheet 10 is provided with a window 13 through which suitable inscriptions (not shown upon the inner sheet 1 1 may be conveniently examined. Obviously, the number and location of such windows may be varied. Furthermore, in this embodiment the inner sheet 11 has a larger diameter than the rear sheet 12, while the front sheet 10 has a somewhat smaller diameter than the rear sheet 12. Obviously, the diameters of the sheets may be varied at will.

In making the assembly, the sheets 10, 11 and 12 are initially provided with the required printing (not shown). Then the inner sheet 11 is subjected to a cutting operation by any suitable cutter, press or the like (not shown) as the result of which a circular slit 14 is provided in the central portion of the sheet. The center of the slit 14 must coincide with the center of the sheet 11. The slit 14 is so cut that thin strips 15 connect the central disc 16 enclosed by the slit with the rest of the sheet 11 (FIG. 3). Then layers of glue 17 are used to connect the disc 16 with the adjacent surfaces of the front sheet 10 and the rear sheet 12.

As already stated, the glue may be applied in several different ways. In the illustrated embodiment, a layer of glue 17 is applied to a central portion 18 of the inner surface of the front sheet 10, whereby care must be taken that the portion 18 should be precisely equal to and located precisely opposite the disc 16 (FIG. 4). The same central portion of the inner surface of the rear sheet 12 is coated with glue in the same manner and then the front sheet 10 and the rear sheet 12 are pressed against the inner sheet 1 1.

Obviously, the opposite surfaces of the disc 16 may be coated with layers of glue l7 and then the application of glue to the inner surfaces of the sheets 10 and 12 will not be necessary.

When certain types of glue are used, it may be necessary to apply the glue to opposite surfaces of the disc 16 and to inner surfaces of the sheets 10 and 12 as well.

Finally, the glue may be replaced by heat sealing or other suitable means.

When the glue is solidified, a slight turning of the central sheet 11 will tear the strips 15 and then the central disc 16 will act as a pivot around which the inner sheet 11 can be rotated.

It is apparent that this pivot will not be visible from the outside, that it will not be touched by the user and that it will provide efiective means for rotating the inner sheet 11 relatively to the front and rear sheets.

In the above described construction, three sheets 10, 11 and 12 are used. Theoretically, it is possible to use only the sheets 10 and 11 and to eliminate the rear sheet. However, then there is the danger that the sheet 1 1 will drop off the disc 16. In the construction shown in FIG. 5, this possibility is eliminated by providing a small rear cover 19 attached by glue 17 to the disc 16. Then, for all practical purposes, the assembly will consist of only two sheets.

In the construction shown in FIG. 6 the front sheet 20 is provided with a depressed projecting portion 21 which is equal to and in alignment with the central disc of the inner sheet 11. The rear sheet 22 is provided with a similar depressed portion 23. The two portions 21 and 23 are directed toward the central disc and then are joined to the central disc by layers of glue 17 or the like. The advantage of this construction is that the inner sheet 11 will be somewhat spaced from the front and rear sheets so that it can be conveniently rotated without any friction.

I claim:

1. A sheet assembly comprising a front sheet, a rear sheet and an inner sheet located between said front sheet and said rear sheet, said sheets being disk shaped, said inner sheet having a larger diameter than said front and rear said inner sheet having a plurality of arcuate slits positioned so as to form a substantially continuous circle, said slits defining the outer periphery of a central disk which remains attached to the inner sheet by a plurality of thin strips, said inner disk being of shearable material, of glue covering both sides of said central disc and engaging corresponding inner surfaces of said front sheet and said rear sheet, so that uponrelative movement between inner sheets and the front' and rear sheets the thin strips will shear whereby the outer portion of said inner sheet is rotatable around said central disc relatively to said front sheet and said inner sheet, said front sheet having at least one window, the outer portion of said inner sheet carrying inscriptions visible through said window upon rotation of the inner sheet.

2. A sheet assembly in accordance with claim 1, wherein said front sheet and said rear sheet have inwardly projecting portions firmly connected to opposite surfaces of said central disc.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No- 3.604.134 Dated September 14, 1971 Inventor(s) Char] es E c ark It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown belpw:

in claim 1; on line 4, after "rear" insert sheets,

and on line 9, after "material", insert and layers Signed and sealed this 7th day of January 3975.

(SEAL) fittest:

McCOY M. GIBSON JR. C. MARSHALL DANN Atteating Officer Commissioner of Patents 

1. A sheet assembly comprising a front sheet, a rear sheet and an inner sheet located between said front sheet and said rear sheet, said sheets being disk shaped, said inner sheet having a larger diameter than said front and rear said inner sheet having a plurality of arcuate slits positioned so as to form a substantially continuous circle, said slits defining the outer periphery of a central disk which remains attached to the inner sheet by a plurality of thin strips, said inner disk being of shearable material, of glue covering both sides of said central disc and engaging corresponding inner surfaces of said front sheet and said rear sheet, so that upon relative movement between inner sheets and the front and rear sheets the thin strips will shear whereby the outer portion of said inner sheet is rotatable around said central disc relatively to said front sheet and said inner sheet, said front sheet having at least one window, the outer portion of said inner sheet carrying inscriptions visible through said window upon rotation of the inner sheet.
 2. A sheet assembly in accordance with claim 1, wherein said front sheet and said rear sheet have inwardly projecting portions firmly connected to opposite surfaces of said central disc. 